When you have too much to fit on one page, Excel inserts automatic page breaks.  As a result, information that should appear together, may be forced onto different pages.  To control where the breaks appear, you can insert manual page breaks or adjust the automatic ones.

You can see the page breaks if you switch to Page Break view.  Either click the Page Break Preview button to the right of the Status bar at the bottom of the screen (next to your Zoom slider); or, go to the View tab > Workbook views grouping > Page Break Preview button.

When in Page Break preview, the blue lines represent the page breaks.  If you hover over the horizontal or vertical lines, your cursor will change into a double-headed arrow and you can adjust them by clicking and dragging to the appropriate location.

To add a page break:

Select the first cell you want to appear on the new page

Right-click and select Insert Page Break.

To remove a page break:

Simply click on the blue line and drag it either horizontally down off the page, or vertically off to the side.

To get back to the Normal view of the worksheet, select the Normal button to the left of the Page Break Preview button, or, go to the View tab > Workbook views grouping > Normal button.